1. General description
The 74HC245; 74HCT245 is a high-speed Si-gate CMOS device and is pin compatible with Low-Power Schottky TTL (LSTTL).
The 74HC245; 74HCT245 is an octal transceiver featuring non-inverting 3-state bus compatible outputs in both send and receive directions. The 74HC245; 74HCT245 features an output enable input (OE) for easy cascading and a send/receive input (DIR) for direction control. OE controls the outputs so that the buses are effectively isolated.
The 74HC245; 74HCT245 is similar to the 74HC640; 74HCT640 but has true (non-inverting) outputs.
2. Features
■ Octal bidirectional bus interface
■ Non-inverting 3-state outputs
■ Multiple package options
■ Complies with JEDEC standard no. 7A
■ ESD protection:
◆ HBM EIA/JESD22-A114-B exceeds 2000 V
◆ MM EIA/JESD22-A115-A exceeds 200 V
■ Specified from −40 °C to +85 °C and from −40 °C to +125 °C
3. Quick reference data
GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns
| Symbol |
Parameter |
Conditions |
Min |
Typ |
Max |
Unit |
| Type 74HC245 |
| tPHL, tPLH |
propagation delay
An to Bn or Bn to An
|
CL = 15 pF;
VCC =5V
|
- |
7 |
- |
ns |
| CI |
input capacitance |
|
- |
3.5 |
- |
pF |
| CI/O |
input/output capacitance |
|
- |
10 |
- |
pF |
| CPD |
power dissipation capacitance per
transceiver
|
VI = GND to VCC |
[1] - |
30 |
- |
pF |
| Type 74HC245 |
| tPHL, tPLH |
propagation delay
An to Bn or Bn to An
|
CL = 15 pF;
VCC =5V
|
- |
10 |
- |
ns |
| CI |
input capacitance |
|
- |
3.5 |
- |
pF |
| CI/O |
input/output capacitance |
|
- |
10 |
- |
pF |
| CPD |
power dissipation capacitance per
transceiver
|
VI = GND to
VCC − 1.5 V
|
[1] - |
30 |
- |
pF |
[1] CPD is used to determine the dynamic power dissipation (PD in µW):
PD = CPD × VCC2 × fi × N + ∑ (CL × VCC2 × fo) where:
fi = input frequency in MHz;
fo = output frequency in MHz;
CL = output load capacitance in pF;
VCC = supply voltage in V;
N = number of inputs switching;
∑ (CL × VCC2 × fo) = sum of outputs.
4. Functional diagram
Product Tags:
|
|
Octal bus transceiver Integrated Circuit Chip 3-state 74HC245PW,118 Images
|
